Electroretinogram assessment of children with sensorineural hearing loss: implications for screening.

BACKGROUND: The guidelines of the National Deaf Children's Society recommend that children with sensorineural hearing loss (SNHL) be routinely screened for ophthalmological problems and suggest electroretinography (ERG) to exclude Usher syndrome. The present study reports the nature and prevalence of abnormal ERG findings in a cohort of children with SNHL undergoing ERG with the aim of identifying risk factors for the diagnosis of Usher syndrome. METHODS: The medical records of children (<18 years of age) with SNHL referred for ERG at Moorfields Eye Hospital, London, between January 2009 and December 2011 were retrospectively reviewed. Patients were included if they had been referred with SNHL by an audiological medicine consultant and the primary indication for electrodiagnostic testing was possible Usher syndrome. RESULTS: A total of 84 cases met inclusion criteria of which 13 (15%) had ERG findings showing rod-cone dysfunction consistent with a diagnosis of Usher syndrome. Two patients with retinal pigmentary changes had normal ERGs and were diagnosed with rubella retinopathy based on the clinical findings. Risk factor analysis showed that age of ≥8 years at the time of ERG, sex, and bilateral hearing loss were not predictive of a diagnosis of Usher syndrome. However, the presence of or referral for cochlear implants, having relevant symptoms and/or clinical signs consistent with a retinal dystrophy, and profound hearing loss were all highly predictive. CONCLUSIONS: ERG is a useful diagnostic tool in children with SNHL and should be performed in children with SNHL who have cochlear implants and/or have signs or symptoms of retinal dystrophy. A focused approach could have potential cost-saving benefit.

Cost-effectiveness analysis of clinic-based chloral hydrate sedation versus general anaesthesia for paediatric ophthalmological procedures.

BACKGROUND/AIMS: The inability of some children to tolerate detailed eye examinations often necessitates general anaesthesia (GA). The objective was to assess the incremental cost effectiveness of paediatric eye examinations carried out in an outpatient sedation unit compared with GA. METHODS: An episode of care cost-effectiveness analysis was conducted from a societal perspective. Model inputs were based on a retrospective cross-over cohort of Canadian children aged <7 years who had both an examination under sedation (EUS) and examination under anaesthesia (EUA) within an 8-month period. Costs ($CAN), adverse events and number of successful procedures were modelled in a decision analysis with one-way and probabilistic sensitivity analysis. RESULTS: The mean cost per patient was $406 (95% CI $401 to $411) for EUS and $1135 (95% CI $1125 to $1145) for EUA. The mean number of successful procedures per patient was 1.39 (95% CI 1.34 to 1.42) for EUS and 2.06 (95% CI 2.02 to 2.11) for EUA. EUA was $729 more costly on average than EUS (95% CI $719 to $738) but resulted in an additional 0.68 successful procedures per child. The result was robust to varying the cost assumptions. CONCLUSIONS: Cross-over designs offer a powerful way to assess costs and effectiveness of two interventions because patients serve as their own control. This study demonstrated significant savings when ophthalmological exams were carried out in a hospital outpatient clinic, although with slightly fewer procedures completed.

Survey of policy for MRSA screening in English cataract surgical units and changes to practice after updated National guidelines.

BACKGROUND: National guidelines on MRSA (methicillin-resistant Staphylococcus aureus) screening policy in England have changed on a number of occasions, but there is limited data on its influence at a local level. The aim of this study was to determine if changes in National policy influenced preoperative screening of cataract patients for MRSA. METHODS: A structured telephone survey was conducted on all 133 ophthalmology units in England in 2004 and again in 2007 for the initial responders, after a change in national policy. RESULTS: A total of 74 units (56%) responded in 2004 and 71 units (96% of initial respondents) in 2007. In 2004, 57% of units screened for MRSA. They screened groups at high risk of carriage, including patients with previous MRSA (93%) and patients from Nursing homes (21%). Swab sites included the nose (100%), eyes (31%) and perineum (62%). In 2007, there was no significant change in the number of units that screened for MRSA (57% vs 66%; p = 0.118; McNemar test). However, more units screened for MRSA in patients from nursing/residential homes (21% vs 51%; p = 0.004, McNemar test), and in patients who had recent admission to hospital (12% vs 36%; p = 0.003). In the second survey, 3 units (6%) now screened patients who were close relatives of MRSA carriers. CONCLUSION: This survey has highlighted inconsistences in MRSA screening practice of day-case cataract surgery patients across England after 2 major national policy changes. A change in DoH policy only led to more units screening patients for MRSA from high risk groups.

Utilisation of an outpatient sedation unit in paediatric ophthalmology: safety and effectiveness of chloral hydrate in 1509 sedation episodes.

OBJECTIVE: To report the largest study on the safety and effectiveness of sedation in paediatric ophthalmology in a nurse-led outpatient sedation unit. DESIGN: Retrospective cohort study reviewing all children who underwent sedation from January 2006 to December 2010. Patients were sedated with 80 mg/kg of chloral hydrate (CH) given orally with top up dose given at half dose as required. All demographic data, sedation and procedure duration, sedation success and adverse events were recorded. Univariate and multiple regression analyses were performed to assess factors associated with success and complications. RESULTS: Data was collected for 1509 sedation episodes. More boys were sedated compared with girls (56.3% vs 43.7% p=0.0003) with an average age of 23.86 months and weight of 11.76 kg. A higher proportion of patients had an American Society of Anaesthesiologists status of II than I (58.5%:41.5%, p=0.0001). Successful sedation was obtained in 96.69% of children with 4.77% requiring a top up dose to achieve this. The average sedation duration was 53.4 min (SD=21.5) with an average of 1.7 procedures performed; the most common being a detailed examination (93.5%) and electroretinogram (45.1%). Adverse events included paradoxical reaction (1.33%), oxygen desaturation (0.99%) and vomiting (0.53%). There were no serious complications or hospital admission. Multiple logistic regression analysis found weight greater than 15 kg and needing a top up dose to be significant risk factors for Failure (OR=2.49 and 8.69, respectively) and Adverse events (OR=2.1 and 3.97, respectively). Sex and American Society of Anesthesiologists Physical Status score did not significantly affect outcomes. CONCLUSIONS: CH sedation allows detailed examination and investigations in the majority of children with few side effects. Patients over 15 kg and need for a top up dose are risk factors for failure and adverse events. This is the largest study in the current literature looking at the use of CH sedation in ophthalmology and confirms its safety and effectiveness.

ß-Defensin 1 haplotype associated with postoperative endophthalmitis.

PURPOSE: Endophthalmitis is a rare but sight-threatening complication of intraocular surgery. ß-Defensins are antimicrobial peptides that appear to be important components of the ocular immune response. We propose that variation in defensin genes may alter susceptibility to endophthalmitis. METHODS: Post-cataract endophthalmitis patients (n = 28) and post-cataract controls (n = 75) were recruited and DNA samples extracted. The ß-defensin 1 gene (DEFB1) was screened for single-nucleotide polymorphisms (SNPs) using bidirectional sequencing. Case-control statistical assessment was undertaken for both the individual polymorphic loci observed and combined haplotypes using PHASE software. RESULTS: We identified 19 SNPs and observed strong linkage disequilibrium within the gene. We found that the three-SNP haplotype -688C/-44C/-20A was associated strongly with endophthalmitis [odds ratio (OR) = 8.88 (1.74, 45.42), corrected p = 0.0095]. Furthermore, we uncovered several trends, including increased prevalence of the -44CC genotype in the endophthalmitis group. CONCLUSION: We have shown previously that the -44CC SNP genotype was present in a single case of bilateral endophthalmitis. In this study, we found this genotype to be more common in the endophthalmitis group and a mini-haplotype including this SNP was associated strongly with endophthalmitis. There is functional evidence that this genetic profile decreases transcription of the ß-defensin 1 peptide and could therefore reduce the innate ocular immune defence.

Leigh's disease associated with a dorsal midbrain syndrome.

Leigh's disease is a rare progressive neurodegenerative condition caused by a mitochondrial cytopathy. The authors present the case of a 9-year-old girl with dorsal midbrain syndrome causing convergence retraction nystagmus. Magnetic resonance imaging, skin biopsy, and genetic testing confirmed the cause to be Leigh's disease due to two SURF1 mutations. To the authors' knowledge, this is the first reported case of dorsal midbrain syndrome caused by a mitochondrial cytopathy.

Pseudomonas aeruginosa eyelid necrosis associated with Felty syndrome.

We describe a case of left upper eyelid necrosis due to Pseudomonas aeruginosa in a patient with Felty syndrome. This is a rare but potentially serious condition. In our patient, medical management and reconstructive surgery achieved a good outcome.